Touch screens allow a user to conveniently interface with an electronic display system. For example, a user can carry out a complicated sequence of instructions by simply touching the screen at a location identified by a pre-programmed icon. The on-screen menu may be changed by re-programming the supporting software according to the application.
Resistive and capacitive are two common touch sensing methods employed to detect the location of a touch input. A touch location is generally determined by applying an electric field to a resistive film in the touch sensitive area. For an electrically continuous resistive film, the accuracy of detecting the location of an applied touch typically depends on the linearity of the electric field in the resistive film. The electric field linearity is typically improved by forming an electrode pattern around the touch sensitive area.